CXCR6 and neoplasm: These changes included downregulated S1PR1 and CXCR1 and increased expression of CXCR5, CXCR6, and CXCL13 compared with non-tumor NK cells.211 In an orthotopic mouse lung tumor model, mature circulating NK cells migrated to tumor-bearing lungs in a CXCR3-dependent manner.